What is the legal minimum age to possess a shotgun or rifle in Nebraska, without adult supervision?

In the state of Nebraska, the minimum age to possess a shotgun or rifle without adult supervision is 18 years old. This means that anyone under the age of 18 must have adult supervision while handling these types of firearms. Option A is incorrect because 16 years old is not the legal minimum age in Nebraska. Option C is also incorrect because 21 years old is the minimum age for purchasing a handgun in Nebraska, but it is not specifically for possessing a shotgun or rifle. Option D is incorrect because there is a minimum age requirement in Nebraska for possessing these types of firearms.